A tragedy that shocked the world captures headlines in Britain as national newspapers add their voices to the wave of condemnation for the New Zealand mosque shootings.

The deaths of 49 people at two mosques in the city of Christchurch are described as “heinous murder” and “an act of savagery”, while social media firms also come under scrutiny after a gunman appeared to have live-streamed the terror attack.

The Times calls the massacre “pure wickedness” and echoes New Zealand prime minister Jacinda Ardern’s words on those affected by the tragedy, saying: “They are us”.

“Those threatened by hatred and xenophobia are not outsiders but fellow citizens,” it writes. “Their welfare and safety are indivisible from all others in a free society.”

The paper also urges technology giants to crack down on the ability to use their platforms for “inhuman ends”, writing in its leader: “Terrorists in the digital age are able to combine ancient notions of the ‘propaganda of the deed’ with the means of broadcasting their crimes.”

The Daily Telegraph warns that social media firms get off too lightly when inappropriate content is posted on their sites.

“One cannot stop the technological change in communications, but it comes with ethical responsibility – and if ethics are not exercised then laws have to be written to enforce them,” it says.

“Blame for this horrendous slaughter lies squarely with the killer, obviously. But he was consciously pursuing a strategy of tension, trying to intimidate and terrify society into chaos and overreaction and, in the sense that social media was the medium by which he spread his frightening message, it has become an unwitting tool of extremists.